Determination of ethylenediaminetetraacetic acid (EDTA) in pharmaceutical dosage forms using flame atomic absorption spectroscopy

In this study, flame atomic absorption spectroscopy coupled with the ion-exchange technique was adopted for the determination of ethylenediaminetetraacetic acid (EDTA) in certain dosage forms. The method is based on complexation of EDTA with an excess of calcium(II) or magnesium( II) at pH 10. The remaining metal ions were fixed on a cationic ion- exchange resin, while Ca-EDTA or Mg-EDTA sequestrates were eluted. The eluted sequestrates were determined using flame atomic absorption spectroscopy. The experimental conditions were carefully studied, and the method was applied for the determination of EDTA. over the concentration ranges of 4-160 and 2-32 mu g ml(-1) upon using Ca(II) and Mg(II), respectively. The proposed method was successfully applied for the determination of EDTA in pharmaceutical dosage forms. The proposed method is characterized by high sensitivity, satisfactory accuracy and precision. (C) 1998 Elsevier Science S.A. All rights reserved.